This invention relates to inserter systems which assemble batches of documents, which may be sheets and/or forms, for insertion into envelopes. More particularly it relates to control systems for such inserter systems. (By sheets herein is meant single sheet documents and by forms herein is meant documents which comprise a web and which are separated from such web by such inserter systems).
Such systems are known in the art and are generally used by organizations which make large mailings where the contents of each item mailed may vary. Such systems typically comprise: feeder modules for insertion of sheets into a batch, either multiply or singly; web modules for separating webs into discrete forms and inserting the discrete forms into the batch; envelope modules for inserting the batches into envelopes; a transport system for conveying sheets and forms through the various modules to form proper batches; inserter modules for inserting the batches into envelopes, which are preferably preaddressed; optionally, meter modules for metering the envelopes with appropriate postage; and a control system to synchronize the operation of the inserter system to assure that the batches are properly assembled, inserted into envelopes, and, possibly, metered.
Information for control of such known inserters system is read from a control document, which is preferably a form, by a scanner associated with the feeder module or web module which feeds that document. Preferably that module is the most upstream module along the transport system. The scanner reads information from the control document which typically includes information such as information defining the number of documents to be inserted at each module, information providing an I.D. code for comparison with I.D. codes on inserted documents to assure that documents are properly matched, and, possibly, information for other purposes such as selection of postage. This control information is then transmitted to the control system which controls the operation of the inserter system accordingly to assure the proper assembly and processing of each batch as defined by a control document.
As noted above control documents are preferably forms since compilation of the control information for each batch is most readily done through data processing with output through a line printer onto a web of computer printout forms. Accordingly, inserter systems generally comprise an upstream web module, or modules, which feed accumulations of forms (i.e., a control form and optionally, one or more succeeding non-control forms from the web) into a sheet inserter system; including feeder modules, inserter modules and, possibly, postage meter modules, where appropriate sheets would be inserted to complete the batch, the batch inserted into an envelope, and, possibly, postage indicia imprinted. Such sheet inserter systems are known and typical examples are described in U.S. Pat. No. 3,606,728; issued: Sept. 21, 1971; to: Sather et al; assigned to Bell and Howell Co.; and U.S. Pat. No. 3,955,429; issued Jan. 27, 1976; to: Braneky et al; assigned to: Pitney Bowes Inc.
Web modules comprise a forms feeder which feeds a web of forms into a burster-folder, where the web is separated into discrete forms, which may be folded to fit into an envelope, if necessary, and a scanner which reads information from the web before bursting. To prevent accidental premature bursting a slack loop of web is maintained between the forms feeder and the burster-folder
Typically, before the web is fed into the burster-folder the forms feeder removes the sprocket strips, which are used to drive the web, from the web. Accordingly, in systems where control information is printed on the sprocket strips (in order not to print extraneous information on the form to be mailed) the scanner must be positioned to scan the web before the sprocket strips are removed.
Web modules may also include an accumulator which accumulates a number of succeeding non-control forms with a control form and then feeds the accumulation into a batch.
The mechanical construction and operation of web modules is well understood by those skilled in the art as is, as mentioned above, the control, construction and operation of conventional sheet inserter systems. U.S. Pat. No. 4,395,255; issued: July 26, 1983; to: Braneky et al; assigned to: Pitney Bowes Inc. teach typical web handling equipment. Further discussion of sheet inserter systems and the mechanical aspects of web modules used in embodiments of the subject invention is not believed necessary for an understanding of the subject invention as described below and will not be discussed further herein.
Such systems have in the past proved satisfactory for the automatic assembly of large mailings of varying items. They have, however, suffered from the disadvantage of an inflexible control structure, typically implemented with discrete hardwired logic, which was substantially limited in selection of configurations. (By configuration herein is meant parameters defining various aspects of the format of the control information for a mailing which might include aspects such as form length, positioning of control information on the control document, the meaning of particular codes used to express the control information, the identity of the module which feeds the control document, and/or the number of forms needed in the slack loop.) Further, to the extent configurations could be changed such changes were complexed operations typically requiring the operator to make adjustments at various modules.
Another problem was found in previously known inserter systems of the type wherein control information was printed on the sprocket strips. When an operator would halt the system in the middle of a mailing the system would complete operations on an item in process before halting. But frequently control forms with the sprocket strips, and the control information printed thereon, removed would be halted in the web loop. Thus, restarting the system to process these stripped control documents was a complex and difficult process.